Rapid Determination of Iodine Value and Saponification Value of Fish Oils by Near‐Infrared Spectroscopy

A rapid method for determining the iodine value (IV) and saponification value (SV) offish oils has been developed using near‐infrared (NIR) spectroscopy. The partial least squares (PLS) calibration model was made based on a spectral range between 7560 and 9100 cm −1 due to CH bond. The method was validated by comparing the IV and SV of a series of fish oils predicted by the PLS model to the values obtained by the titration methods of the Japan Oil Chemists' Society. The NIR‐predicted IV and SV were completely consistent with chemically determined IV and SV. The NIR method showed higher accuracy and reproducibility than the titration method. It would be suitable for IV and SV determinations offish oils, as well as vegetable oils, and it takes only 2 min per sample.